Climate change is already affecting both natural and human systems in the United States and around the world. As greenhouse gas emissions from human activities continue to rise, the impacts of climate change are expected to become even stronger and more evident. For the first time in the history of civilization, we have reached a point where value of future planning in a broad range of sectors, including agriculture, water resources, and even tourism, depends on our ability to quantify the impacts of climate change at the regional scale. Developing high-resolution projections, however, is a challenging task. In addition to complex modeling tools and prohibitive computational demands, it also requires a solid understanding of the uncertainties and errors involved in this process. The enigmas of population growth and energy demand, the complexities of the physical climate system, and the intricacies of the statistical methods used to downscale global projections all contribute to blurring future projections. Drawing on examples from my research, I will illustrate how these and other sources of error and uncertainty can be quantified and incorporated into assessing a broad range of potential climate impacts, from cotton yields in West Texas to the ski industry in New Hampshire.